testing/grok: new aport

https://code.google.com/archive/p/semicomplete/wikis/Grok.wiki A powerful pattern-matching/reacting tool.

Note, that grok is 'old' and their build system is a bit messy. So the patch introduces some oddities for sure, a necessary evil.

Depends on !31799 (closed)

Signed-off-by: Olliver Schinagl oliver@schinagl.nl